Aortic valve-sparing root replacement with Tirone E. David's reimplantation technique: single-centre 25-year experience

Valve-Sparing Aortic Root Replacement State-of-the-Art Review, Part I: Anatomy and Physiology

Aortic valve disease is common, and valve-preserving operations are preferred whenever possible. Valve-sparing aortic root replacement has become an important tool for managing aortic root pathology in children and adults. The learning curve for this operation is challenging, but with increasing experience and technical modifications, early and late outcomes continue to improve. Durable long-term results vary based on the underlying anatomy, pathology, and patient selection, as well as surgeon expertise. The first installment of this Valve-Sparing Aortic Root Replacement State-of-the-Art Review article addresses patient anatomy and physiology as it relates to candidacy for VSRR.

Short and mid-term outcomes of valve-sparing, aortic root reimplantation (David's procedure)

BACKGROUND

In the current study, we aimed to report the short- and mid-term outcomes of patients undergoing valve-sparing aortic root reimplantation (VSARR) and our center's experience with the procedure.

METHODS

Forty patients with aortic root aneurysms underwent VSARR at our center from 2010 until 2022. We retrospectively reviewed the medical records of these patients and extracted the relevant data. After carefully examining the aortic valve, the surgeon decided to perform Bentall or David's procedure during the operation.

RESULTS

The study population comprised 31 (77.5%) men and nine (22.5%) women, with a mean age of 55.35 ± 15.40. One patient developed hemodynamic instability post-surgery in the hospital and died from multi-organ failure. Another patient had severe AI in the intraoperative echocardiography, and aortic valve replacement with a prosthetic graft was performed during the same operation. In pre-operation echocardiography, 25 (62.5%) patients had severe, nine (22.5%) had moderate, and six (15%) had mild AI. In the in-hospital post-operation follow-up echo, AI was improved, and no patients had severe AI (P < 0.001). Only eight patients had moderate AI in post-one-year follow-up echo exams, while the rest had mild AI.

CONCLUSION

David's procedure showed excellent mid-term results in our center, with only one in-hospital mortality.

Aortic Valve-Sparing Operations

Aortic valve-sparing operations were developed >3 decades ago and have become part of the surgical armamentarium to treat patients with aortic root and ascending aortic aneurysms. Although remodeling of the aortic root is physiologically sounder than reimplantation of the aortic valve, most surgeons seem to prefer the latter. This review summarizes the views of one of the pioneers of aortic valve-sparing operation and includes their development, the various modifications that occurred over the years, comparative outcomes with aortic root replacement with valved conduits, outcomes from several recently reported series, and the future directions. The author argues that comparisons between aortic valve-sparing operations and aortic root replacement with valved conduits based on retrospective studies are inappropriate because these 2 types of surgery are performed in patients with different aortic valve pathology. Late outcomes after aortic valve-sparing operations have not been consistent among various reports and raise the question of surgical expertise and patients' selection. Aortic valve-sparing operations are the best treatment for young patients with aortic root aneurysm and normal aortic cusps. Further studies are needed to define their role in the management of patients with diseased aortic cusps.

Outcomes of aortic valve-sparing root replacement with cusp repair in connective tissue disease

BACKGROUND

Although, valve sparing is commonly performed in patients with Marfan syndrome, feasibility and results of cusp repair for aortic insufficiency have not been studied.

AIM

To report on the outcomes and durability of aortic cusp repair in valve sparing in patients with Marfan syndrome.

METHODS

All consecutive adult patients with Marfan syndrome who underwent remodelling and annuloplasty with aortic valve repair for aortic insufficiency between May 2005 and December 2020 were included. Patients with Marfan syndrome treated for aortic aneurysm, but without aortic insufficiency, were excluded. Data were collected prospectively and reviewed retrospectively from the Aorticvalve repair International Registry (AVIATOR).

RESULTS

During the study period, 71 patients with Marfan syndrome were referred to surgery. Fifty-five patients with connective tissue disease and aortic insufficiency with aorta aneurysm were treated: 46 underwent aortic valve repair and nine underwent aortic valve replacement (five mechanical aortic valve replacements and four biological aortic valve replacements). The mean age was 42.9±15.4 years, and the mean EuroScore II was 2.5±2.2. No patient died, and no patient had significant aortic insufficiency (grade≥II) at discharge. The 5-year survival rate estimate was 94.4%, which seems statistically similar to that of the age- and sex-matched general population. At 5 years, freedom from reoperation was 94.6%, and the incidence of infective endocarditis was 2.6%. No valve thrombosis, aortic dissection, major bleeding events, thromboembolic events (stroke) or myocardial infarctions were noted during follow-up.

CONCLUSION

Remodelling and aortic valve repair showed excellent durability at 5 years, even in connective tissue disorders.

Twenty-five year experience with aortic valve-sparing root replacement in a single teaching center

Objectives

Aortic valve-sparing root replacement (AVSRR) is a technically demanding procedure. In experienced centers it offers excellent short- and long-term results, making the procedure an attractive alternative for aortic root replacement especially in young patients. The aim of this study was to analyze long-term results of AVSRR using the David operation in our institution over the last 25 years.

Methods

This is a single-center retrospective analysis of outcomes of David operations performed in a teaching institution not running a large AVSRR-program. Pre-, intra- and postoperative data were collected from the institutional electronic medical record system. Follow-up data were collected through direct contact of the patients and their cardiologists/primary care physicians.

Results

Between 02/1996 and 11/2019, 131 patients underwent David operation in our institution by a total of 17 different surgeons. Median age was 48 (33–59), 18% were female. Elective surgery was performed in 89% of the cases, 11% were operated as emergency in the setting of an acute aortic dissection. Connective tissue disease was present in 24% and 26% had a bicuspid aortic valve. At hospital admission 61% had aortic regurgitation grade ≥3, 12% were in functional NYHA-class ≥III. 30-day mortality was 2%, 97% of the patients were discharged with aortic regurgitation ≤2. In 10-year follow-up, 15 (12%) patients had to be re-operated because of root-related complications. Seven patients (47%) received a transcatheter aortic valve implantation, 8 (53%) required surgical replacement of the aortic valve or a Bentall-De Bono operation. Estimated reoperation-free survival at 5 and 10 years was 93.5% ± 2.4% and 87.0% ± 3.5%, respectively. Subgroup analysis showed no differences in reoperation-free survival for patients presenting with a bicuspid valve or preoperative aortic regurgitation ≥3. However a preoperative left ventricular end diastolic diameter of ≥5.5 cm was associated with worse outcome.

Conclusion

David operations can be performed with excellent perioperative and 10-year follow-up outcomes in centers not running large AVSRR-programs.

Complexity and Outcome of Reoperations After the Ross Procedure in the Current Era

BACKGROUND

The Ross procedure has several advantages, but the need for reintervention is inevitable. The aim of this study was to examine the complexity and outcomes of reoperation after the Ross procedure.

METHODS

Retrospective chart review was performed of patients with a prior Ross procedure who underwent reoperation at our institution from September 1991 to January 2021. Demographic, echocardiographic, surgical, and perioperative data were collected. Descriptive statistical and regression analyses were performed.

RESULTS

A total of 105 patients underwent a reoperation at Mayo Clinic after the initial Ross procedure performed at our institution (n = 16; 16.2%) or elsewhere (n = 83; 83.8%). Mean age at the Ross procedure was 27 ± 17 years, and mean age at reoperation at our institution was 37 ± 19 years. Indications for surgical procedure varied, but 64% had autograft regurgitation as 1 of their indications for reoperation. Autograft interventions were performed in 78 patients (74.2%). Pulmonary valve or conduit replacement was performed in 56 patients (53.3%). Double root replacement was performed in 11 patients (10.5%). Aortic reconstruction was performed in 37 patients (38.4%). There were 5 early deaths (5%). During a median follow-up of 6.25 years (3 months-24 years), late deaths occurred in 14 patients (13.1%). Patients with ejection fraction <30% on preoperative echocardiography had shorter duration between the Ross procedure and subsequent reoperation (P = .03).

CONCLUSIONS

Reoperations after the Ross procedure are performed for a wide range of indications, with most due to autograft dysfunction. The number of early deaths is not low. Reoperation after the Ross procedure should be advised before left ventricular systolic dysfunction.

Current controversies in aortic valve-preserving surgery

The clinical outcome of severe aortic regurgitation (AR) remains suboptimal, but surgery has been shown to have survival benefit over medical therapy. Postoperative survival is inferior in patients with reduced left ventricular function, and therefore early surgical intervention is recommended. Aortic valvuloplasty (AVP) is an attractive option to avoid the major drawbacks of prosthetic valves but has not been widely adopted. The etiology of AR is classified functionally into three groups: normal leaflet motion (type I), cusp prolapse (type II), and restriction (type III). Type I with dilatation of the sinus of Valsalva (type Ib) can be repaired by aortic valve reimplantation or aortic root remodeling with similar valve stability. Type I with dilatation of the aortic annulus (type Ic) can be managed by annuloplasty. Type II can be corrected by plication or resuspension techniques. Pericardial patch is necessary in AVP for type Id (perforation/fenestration) and type III but is associated with risk of recurrence. Bicuspid aortic valve is classified according to commissure angle: symmetrical, asymmetrical, and very asymmetrical. Tricuspidization is recommended for repair of very asymmetrical valves to avoid postoperative stenosis. Recent progress has achieved similar reoperation rates between bicuspid and tricuspid aortic valve repair. For Marfan syndrome, valve-sparing root replacement is advantageous compared to Bentall operation regarding late survival, thromboembolic and hemorrhagic events, and endocarditis. Similar findings have been reported in acute aortic dissection. Both remodeling and reimplantation procedures provide similar favorable outcomes in these settings. Recent advances in AVP are summarized by quantitative assessment of cusp configuration (effective height and geometric height), graft size decision, use of template to cut the graft, and videoscopic assessment of post-repair cusp configuration. Due to these advances, AVP shows superior results to replacement surgery. Further concrete evidence with larger case volumes and longer observation periods are necessary to popularize AVP.

Outcomes of Reimplantation of the Aortic Valve in Patients With Aortic Cusp Fenestration

BACKGROUND

Aortic cusp fenestrations are common in patients with aortic root aneurysm, and their management during aortic valve repair remains controversial. We believe that fenestrations in the area of the commissures may rupture after reimplantation of the aortic valve because this operation increases the mechanical stress on the cusps. For this reason we have reinforced the free margin of the aortic cusp with fenestration with fine Gore-Tex sutures (WL Gore). This study examines the outcomes of reimplantation of the aortic valve in patients who had cusp fenestration reinforced with Gore-Tex sutures.

METHODS

A review of all patients who had reimplantation of the aortic valve for aortic root aneurysm disclosed 111 patients who had at least 1 cusp fenestration reinforced with a double layer of a fine Gore-Tex suture. The outcomes of these patients were examined and compared with a group of patients without fenestration using propensity score analysis. All patients were followed prospectively with images of the heart.

RESULTS

The median follow-up was 8.3 years. Overall the cumulative incidence of aortic valve reintervention at 15 years was 4.8% and the cumulative incidence of aortic insufficiency of moderate or severe degree was 9.2%. Comparison of outcomes of patients with and without fenestrations showed similar results up to 15 years of follow-up.

CONCLUSIONS

Reinforcement of the free margins of cusps with fenestrations using Gore-Tex sutures is safe and does not seem to adversely affect the durability of reimplantation of the aortic valve.

Valve-sparing David procedure via minimally invasive access does not compromise outcome

Objectives

Aortic valve sparing-aortic root replacement (David procedure) has not been routinely performed via minimally invasive access due to its complexity. We compared our results of elective David procedure via minimally invasive access to those via a full sternotomy.

Methods

Between 1993 and 2019, a total of 732 patients underwent a valve sparing root replacement (David) procedure. Out of these, 220 patients underwent elective David-I procedure (isolated) without any other concomitant procedures at our center. Patients were assigned to either group A (n = 42, mini-access) or group B (n = 178, full sternotomy).

Results

Cardiopulmonary bypass time were 188.5 ± 35.4 min in group A and 149.0 (135.5–167.5) in group B (p < 0.001). Aortic cross-clamp time were 126.2 ± 27.2 min in group A and 110.0 (97.0–126.0) in group B (p < 0.001). Post-operative echocardiography showed aortic insufficiency ≤ I° in 41 (100%) patients of group A and 155 (95%) of group B. In-hospital mortality was 2.4% (n = 1) in group A and 0% (n = 0) in group B (p = 0.191). Perioperative stroke occurred in 1 (2.4%) patient of group A and 2 (1.1%) patients of group B (p = 0.483). Reexploration for bleeding was necessary in 4 (9.5%) patients of group A and 7 (3.9%) of group B (p = 0.232). Follow-up was complete for 98% of all patients. The 1-, 2-, 4-, and 6-year survival rates were: 97, 97, 97, and 97%, in group A (mini-access) and 99, 96, 95, and 92% in group B (full sternotomy), respectively. The rates for freedom from valve-related re-operation at 1, 2, 4, and 6 years after initial surgery were: 97, 95, 95, and 84% in group A and 97, 95, 91, and 90% in group B, respectively.

Conclusion

Early post-operative results after David procedure via minimally invasive access are comparable to conventional full sternotomy. Meticulous attention to hemostasis is a critical factor during minimally access David procedures. Long-term outcome including the durability of the reimplanted aortic valve seems to be comparable, too.

Valve-sparing Root Reimplantation In Patients With Left Ventricular Dilation

OBJECTIVES

The purpose of this study was to evaluate the association between left ventricular (LV) dilation and outcomes following valve-sparing root reimplantation.

METHODS

Patients with an indexed left ventricular internal diameter during systole (iLVIDS) of ≥ 2.0 cm/m2 were categorized as having LV dilation. Outcomes were post-operative aortic insufficiency (AI), re-intervention, and all-cause mortality. The cumulative incidence of each outcome was computed using the Kaplan-Meier estimator. Adjusted comparisons between strata were performed for each outcome using a Cox proportional-hazards model. Where possible, the competing risk of death was accounted for. Multilevel mixed-effects ordered logistic regression was performed for AI grade at follow-up.

RESULTS

There were 295 patients of whom 52 had LV dilation. Operative outcomes were excellent; there were no significant differences between groups. Patients with LV dilation demonstrated significant improvement in iLVIDS overtime. There was no association between LV dilation and post-operative AI grade >2 (HR 0.88, 95% CI 0.21 to 3.67, p = 0.89) or odds of increased AI grade overtime (OR = 0.76, 95% CI 0.30 to 1.93, p = 0.57). There were no re-interventions among those with LV dilation. Adjusted mortality was significantly higher among those with LV dilation (HR 5.56, 95% CI 1.56 to 19.9), however, deaths were unrelated to aortic valve dilation.

CONCLUSIONS

Left ventricular dilation is not associated with poorer operative outcomes, post-operative AI, or re-intervention. It is associated with increased risk of mortality, though not from valvular dysfunction. LV dilation should not deter VSRR when otherwise indicated.

A Novel Device for Intraoperative Direct Visualization of a Pressurized Root in Aortic Valve Repair

PURPOSE

One major challenge in generating reproducible aortic valve (AV) repair results is the inability to assess AV morphology under physiologic pressure. A transparent intraoperative aortic valve visualization device was designed and manufactured.

DESCRIPTION

This device is comprised of an open proximal end, a cantilevered edge to allow attachment of the device to the aorta or graft, a distal viewing surface, and two side ports for fluid delivery and air removal.

EVALUATION

The performance of the device was evaluated ex vivo using normal porcine AV in situ (n=3), AV after valve-sparing aortic root replacement (VSARR, n=3), and porcine pulmonary valve in Ross procedure (n=3), and in 3 patients who underwent VSARR. AV morphology was clearly visualized using the device in all experiments. In human, the use of this device successfully illustrated cusp prolapse after the initial VSARR and effectively guided additional cusp repair.

CONCLUSIONS

This device successfully allows for direct visual assessment of the AV apparatus under physiologic pressure. The use of this device can potentially increase the adoptability of AV repair in clinical practice.

Midterm outcomes of aortic root surgery in patients with Marfan syndrome: A prospective, multicenter, comparative study

OBJECTIVE

The objective of this study was to compare midterm outcomes of aortic valve-replacing root replacement (AVR) and aortic valve-sparing root replacement (AVS) operations in patients with Marfan syndrome.

METHODS

Patients who met strict Ghent diagnostic criteria for Marfan syndrome and who underwent either AVR or AVS between March 1, 2005 and December 31, 2010 were enrolled in a 3-year follow-up prospective, multicenter, international registry study; the study was subsequently amended to include 20-year follow-up. Enrollees were followed clinically and echocardiographically.

RESULTS

Of the 316 patients enrolled, 77 underwent AVR and 239 underwent AVS; 214 gave reconsent for 20-year follow-up. The median clinical follow-up time for surviving patients was 64 months (interquartile range, 42-66 months). Survival rates for the AVR and AVS groups were similar at 88.2% ± 4.4% and 95.0% ± 1.5%, respectively (P = .1). Propensity score-adjusted competing risk modeling showed associations between AVS and higher cumulative incidences of major adverse valve-related events, valve-related morbidity, combined structural valve deterioration and nonstructural valve dysfunction, and aortic regurgitation ≥2+ (all P < .01). No differences were found for reintervention (P = .7), bleeding (P = .2), embolism (P = .3), or valve-related mortality (P = .8).

CONCLUSIONS

Five years postoperatively, major adverse valve-related events and valve-related morbidity were more frequent after AVS than after AVR procedures, primarily because of more frequent aortic valve dysfunction. No between-group differences were found in rates of survival, valve-related mortality, reintervention on the aortic valve, or bleeding. We plan to follow this homogenous cohort for 20 years after aortic root replacement.